UNT Libraries Government Documents Department - 198 Matching Results

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The additional-mass effect of plates as determined by experiments

Description: From Introduction: "The apparent increase in the inertia properties of a body moving in a fluid medium has been called the additional-mass effect. This report presents a resume of test procedures and results of experimental determinations of the additional-mass effect of flat plates. In addition to data obtained from various foreign sources and from a NACA investigation in 1933, the results of tests recently conducted by the National Advisory Committee for Aeronautics are included."
Date: 1941
Creator: Gracey, William
open access

Characteristics of Naca 4400R Series Rectangular and Tapered Airfoils, Including the Effect of Split Flaps

Description: "At the request of the Bureau of Aeronautics, Navy Department, tests were made in the variable-density wind tunnel of a tapered wing of 3-10-18 plan form and based on the NACA 4400R series sections. The wing was also tested with 0.2 chord split flaps, deflected 60 degrees, in the center of the wing and having flat span to wing span ratios of 0.3, 0.5, 0.7, and 1.0, respectively" (p. 1).
Date: January 1941
Creator: Greenberg, Harry
open access

Characteristics of NACA 4400R Series Rectangular and Tapered Airfoils, Including the Effect of Split Flaps

Description: "At the request of the Bureau of Aeronautics, Navy Department, tests were made in the variable-density wind tunnel of a tapered wing of 3-10-18 plan form and based on the NACA 4400R series sections. The wing was also tested with 0.2 chord spit flaps, deflected 60 deg span ratios of 0.3, 0.5, 0.7 and 1.0 respectively. In order to get data from which to calculate the characteristics of the flapped wing, the investigation was extended to include tests of the four rectangular airfoils of the NACA 4… more
Date: January 1941
Creator: Greenberg, Harry
open access

Design charts for cross-flow tubular intercoolers charge-across-tube type

Description: Report presenting equations relating the various dimensions, air mass flow, and performance of a cross-flow tubular intercooler in which the charge flows across and the cooling air through the tubes. Design charts are presented from which the intercooler design characteristics and performance can be quickly determined.
Date: January 1941
Creator: Reuter, J. George & Valerino, Michael F.
open access

Determination of control-surface characteristics from NACA plain-flap and tab data

Description: From Summary: "The data from previous NACA pressure-distribution investigations of plain flaps and tabs with sealed gaps have been analyzed and are presented in this paper in a form readily applicable to the problems of control-surface design. The experimentally determined variation of aerodynamic parameters with flap chord and tab chord are given in chart form and comparisons are made with the theory. With the aid of these charts and the theoretical relationships for a thin airfoil, the aerody… more
Date: 1941
Creator: Ames, Milton B., Jr. & Sears, Richard I.
open access

Effect of Alternately High and Low Repeated Stresses Upon the Fatigue Strength of 25S-T Aluminum Alloy

Description: "Fatigue tests were made on one lot of 3/4 inch diameter rolled-and-drawn 25S-T aluminum-alloy rod normal in composition and tensile properties. The specimens were tested at 3500 cycles per second in a rotating-beam fatigue test machine. Tests were made for three ratios (20:1, 50:1, and 200:1) of the number of cycles applied at low stress to the number applied at high stress. In general, failure occurred when the number of cycles at either the low or the high stress approached the ordinary fati… more
Date: January 1941
Creator: Stickley, G. W.
open access

Internal-Flow Systems for Aircraft

Description: An investigation has been made to determine efficient arrangements for an internal-flow system of an aircraft when such a system operates by itself or in combination with other flow systems. The investigation included a theoretical treatment of the problem and tests in the NACA 5-foot vertical wind tunnel of inlet and outlet openings in a flat plate and in a wing.
Date: 1941
Creator: Rogallo, F. M.
open access

Model Tests of a Wing-Duct System for Auxiliary Air Supply

Description: Report discusses the design of a cooling system developed for a Pratt & Whitney H-2800 engine equipped with a two-stage supercharger. The wing-duct system was newly developed and was determined to be a valuable method for cooling engine auxiliaries by combining simplicity with low drag and excellent cooling capabilities.
Date: January 1941
Creator: Bierman, David & Corson, Blake W., Jr.
open access

Shear Lag in Corrugated Sheets Used for the Chord Member of a Box Beam

Description: "The problem of the distribution of normal stress across a wide corrugated sheet used as the chord of a box-beam-like structure is investigated theoretically and experimentally. Expressions are developed giving the stress distribution in beams, symmetrical or unsymmetrical, about a plane passed spanwise through the center of the sheet. The experiments were arranged to insure bending without torsion and surveys of the normal stresses were made by means of mechanical and electrical strain gages" … more
Date: January 1941
Creator: Newell, Joseph S. & Reissner, Eric
open access

Stagnation Temperature Recording

Description: "The present report deals with the development of a thermometer for recording stagnation temperature in compressible mediums in turbulent flow within 1 to 2 percent error of the adiabatic temperature in the stagnation point, depending upon the speed. This was achieved by placing the junction of a thermocouple near the stagnation point of an aerodynamically beneficial body, special care being taken to assure an uninterrupted supply of fresh compressed air on the junction together with the use of… more
Date: January 1941
Creator: Wimmer, W.
open access

Tests of the NACA 0025 and 0035 Airfoils in the Full-Scale Wind Tunnel

Description: This report presents the results of an investigation conducted in the NACA full-scale wind tunnel to determine the aerodynamic characteristics of the 6 by 36-foot rectangular NACA 0025 and 0035 airfoils. The aerodynamic characteristics of the plain airfoils with rounded and square tips were determined by force tests through a complete angle-of-attack range; in addition, the profile drag was determined by the momentum method. The transition points on the airfoils were located by boundary-layer d… more
Date: 1941
Creator: Bullivant, W. Kenneth
open access

Wind-tunnel investigation of NACA 23012, 23021, and 23030 airfoils equipped with 40-percent-chord double slotted flaps

Description: Report presents the results of an investigation conducted in the NACA 7 by 10-foot win tunnel to determine the effect of the deflection of main and auxiliary slotted flaps on the aerodynamic section characteristics of large-chord NACA 23012, 23021, 23030 airfoils equipped with 40-percent-chord double slotted flaps. The complete aerodynamic section characteristics and envelope polar curves are given for each airfoil-flap combination. The effect of airfoil thickness is shown, and comparisons are … more
Date: 1941
Creator: Harris, Thomas A. & Recant, Isidore G.
open access

Determination of optimum plan forms for control surfaces

Description: Solutions found for a range of airfoil plan forms indicate that, regardless of the characteristics of the tail surface, the chord of the rudder or of the elevator should be very nearly constant over its span. The optimum ailerons are also of a characteristic shape, varying little with the plan form of the wing.
Date: January 30, 1941
Creator: Jones, Robert T. & Cohen, Doris
open access

Comparison of Automatic Control Systems

Description: This report deals with a reciprocal comparison of an automatic pressure control, an automatic rpm control, an automatic temperature control, and an automatic directional control. It shows the difference between the "faultproof" regulator and the actual regulator which is subject to faults, and develops this difference as far as possible in a parallel manner with regard to the control systems under consideration. Such as analysis affords, particularly in its extension to the faults of the actual… more
Date: February 1941
Creator: Oppelt, W.
open access

Determination of control-surface characteristics from NACA plain-flap and tab data

Description: From Summary: "The data from previous NACA pressure-distribution investigations of plain flaps and tabs have been analyzed and are presented in this paper in a form readily applicable to the problems of control-surface design. The experimentally determined variation of aerodynamic parameters with flap chord and tab chord are given in chart form and comparisons are made with the theory. With the aid of these charts and the theoretical relationships for a thin airfoil, the aerodynamic characteris… more
Date: February 1941
Creator: Ames, Milton B., Jr. & Sears, Richard I.
open access

Effect of several supercharger control methods on engine performance

Description: Report presenting an analytical comparison of a variety of superchargers using the same hypothetical engine, which include a single-speed, a two-speed, and a variable-speed DVL centrifugal supercharger, the Szydlowski-Planiol supercharger with a single-speed and a two-speed transmission, and a turbosupercharger.
Date: February 1941
Creator: Wasielewski, Eugene W. & King, J. Austin
open access

The End-Plate Effect of a Horizontal-Tail Surface on Vertical Tail Surface

Description: Note presenting the end-plate effect of the horizontal-tail surface on the vertical-tail surface as theoretically studied by derivation of the flow corresponding to the condition of minimum induced drag and by solution of the usual lifting-line equations. The results obtained by the two methods were considerably different, indicated that the condition derived is not a close approximation to the actual condition.
Date: February 1941
Creator: Katzoff, S. & Mutterperl, William
open access

On the Calculation of Flow Past an Infinite Screen of Thin Airfoils

Description: This report deals with the flow past an infinite screen of thin airfoil (two-dimensional problem). The vortex distribution across the profile is established with appropriate expansion in series and the velocity distribution lift, moment, and profile shape deduced. Inversely, the distribution is deduced from the vorticity. The method is the extension of the Birnbaum-Glauert method for the isolated wing.
Date: February 1941
Creator: Pistolesi, E.
open access

Two-Stage Supercharging

Description: "The arrangement of the parts and the installation and control problems of the two-stage mechanically driven superchargers for aircraft engines are discussed. Unless an entirely new form of supercharging is developed, there will be a definite need for a two-stage centrifugal supercharger. It is shown that the two-stage mechanically driven supercharger itself is a comparatively simple device; the complications arise from the addition of inter-coolers and controls" (p. 1).
Date: February 1941
Creator: Buck, Richard S.
open access

Wind-Tunnel Investigation of an NACA 23021 Airfoil With Two Sizes of Balanced Split Flaps

Description: Report presenting an investigation in the 7- by 10-foot wind tunnel of a large-chord NACA 23021 airfoil with a 15-percent-chord and a 25-percent-chord balanced split flap of Clark Y profile, to determine the aerodynamic section characteristics of the airfoil-flap combinations as affected by the size, nose location, and deflection of the flaps.
Date: February 1941
Creator: Swanson, Robert S. & Schuldenfrei, Marvin J.
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